package cn.bellychang.leetcode.question021;

/**
 * @author ChangLiang
 * @date 2021/3/18
 */
public class Solution5 {

    public ListNode mergeTwoLists(ListNode l1, ListNode l2) {

        ListNode head = new ListNode(-1);
        ListNode temp = head;

        while (l1 != null && l2 != null) {
            if (l1.val < l2.val) {
                temp.next = l1;
                l1 = l1.next;
            }else{
                temp.next = l2;
                l2 = l2.next;
            }
            temp = temp.next;
        }
        while(l1!=null){
            temp.next = l1;
            l1 = l1.next;
            temp = temp.next;
        }
        while(l2!=null){
            temp.next = l2;
            l2 = l2.next;
            temp = temp.next;
        }
        return head.next;
    }
}
